Frederick fitt



2 Sheets-Sheet 1.

F. PITT. Removable E soapement'for Watches. No. 230,262. Patented July 20,1880.

hfiinesses. 17 006712 07";

MPETERS. PHOTO-UTHOGRAPHER, WASHINGTON. D. C.

2 Sheets-Sheet 2.

F. PITT. Removable Escapement for Watches. No. 230,262. Patented July 20,1880.

N. PETERS. PHOTO-LITHOGRAFHER. WASHKNG'LUN. D C.

UNITED STATES PATENT OFFICE- FREDERIOK FITT, OF OTTAW A, ONTARIO, CANADA, ASSIGNOR OF A PART OF HIS RIGHT TO JOHN RUTHERFORD ARMSTRONG AND HENRY JAMES GIBBS, OF SAME PLACE.

REMOVABLE ESCAPEMENT FOR WATCHES.

SPECIFICATION-forming part of Letters Patent No. 230,262, dated July 20, 1880.

Application filed February 9, 1880.

To all whom it may concern:

Be it known thatI, FREDERICK Fun, of Ottawa, in the county of Carleton, Province of Ontario, Canada, have invented certain Improvements in Watches, of which the following is a specification.

My invention relates to watches having the escapement mounted wholly upon an independent detachable bed or plate, and is designed as an improvement upon the device for which Letters Patent were granted me bearing date August 24, 1875, and numbered 167,089, the improvements consisting in a pcculiar form and arrangement of parts and location of the fastening-screw, whereby the adj ustment and securing of the escapeinent are rendered more accurate and speedy, the employment of any desired form of escapement permitted, and all danger of disarrangement avoided.

In the accompanying drawings, Figure l is a face view of the watch-movement; Fi 2, a similar view with the escapement removed; Fig. 3, the escapement detached from the movement; Fi 4, the escapement-platform with the eseapement removed therefrom Fig. 5, the reverse or back face of the escapement platform; Fig. 6, a face view of the dial side of the pillar-plate, showing the automatic stop and attendant parts; Fig. 7, a cross-section on the line aas of Fig. 1, showing more clearly the action of the automatic stop; Fig.8, a view of the stop-lever detached; Fig. 9, views representing certain screws hereinafter described Fig. 10, a view of the escapement-platform detached furnished with a straight-line escapemerit.

Under the construction shown in my former patent (above referred to) considerable difficulty was encountered in adjusting the escapement, and occasionally the fastening-screw, striking the face of the detent-lever instead of its edge, would force the same before it, instead of causin git to swingupon its pivot, thereby deranging the parts. The location of the fastening-screw under the former construction and arrangement was also found inconvenient and objectionable, for the reason that it prevented the use of an angular or chronometcr escape ment, and by its proximity to the escapewheel subjected the latter to great danger of injury through the slipping of the tool by which the fastening-screw was turned home.

My present improvements are designed to overcome these difiiculties; and to this end I adopt the construction and arrangement shown in the accompanying drawings, in which A represents the pillar-plate, and B the escapement-platform, having at one end a projecting lip or thin edge, a, and carrying the balance-cock I), the cock-prop being secured in place by a screw, 0, preferably formed with a polygonal head to facilitate its removal by pliers or tweezers.

(1 represents the pallet and escapewheel bracket, also mounted upon the escapementplatform and secured thereto, 0 indicating the balance-wheel,f the pallets, and g the escapewheel.

The several parts being thus mounted and secured upon the plat-form B, it will be seen that in order to remove the escapement it is only necessary to detach the platform from the pillar-plate, when all may be lifted oif.

The manner of secnrin g the platform to the pillar-plate is susceptible of modification; but in practice the arrangement illustrated in the drawings is preferred.

As shown in Fig. 5, the platform B is furnished on its under face with three small projecting studs, h j, which serve as steadyingpins, the pin or stud h being the most important, as it serves to insure and maintain the proper depthing of the teeth in the escape-wh eel pinion. These studs serve to prevent the shifting of the escapement-platform B, which is firmly secured to the pillar'plate by a single screw, It. It will be observed by reference to the drawings that this screw k, instead of bein g located as in the patent above referred to, is located in rear of the balance-cock, whichis thus made to serve as a guard to protect the parts of the escapement against injury through the slipping of the tool by which the screw is inserted. This location of the screw isespecially important, however, in that it permits the use of an angular or a chronometer escapement, which could not be used under the former arrai'igement of parts.

In order that there may be no possibility of the platform B rocking or tipping, a flanged screw, 1, is screwed into the pillar-plate in such position that when the platform is in place its edge or lip a shall extend under the flange of the screw, as shown in Fig. 1.

The screw I need not be removed from the pillar-plate in detaching the escapement-platform, as a very slight backward turn is sufficient to release its hold upon the lip a.

From the above it will be seen that to remove the escapement it is only necessary to loosen the screw l and remove the screw it, when the platform B, with all its attendant parts, may be lifted off.

In order that the connection with the fourth wheel may be easy, the edge of the platform B is recessed, as at m, to fit or pass thereunder, a similar recess, n, being formed on the other face of the platform to accommodate the center wheel, while a projection or lip, 0, at the inner side of the platform B, serves as a convenient hold for the fingers in handling.

The stop or locking device which locks the train automatically upon the detachment of the escapement is represented in position in Figs. 6 and 7 and detached in Fig. 8, it being controlled in its action by the screw it, which holds the platform B in place. While it is preferred to thus control the action of the stop, it is apparent that other means for actuating the same may be employed.

The stop or detent consists of a pin, 17, passing through a slot or opening, 1, in the pillarplate A, and arranged to engage with or be disengaged from the teeth of the fourth wheel, C, said pin being carried upon a pivoted or swinging lever, D, as shown in Figs. 6 and S. The lever D is free to swing or turn upon a shouldered pivotscrew, r, and has its outwardlyq)rqjectin g end shouldered and arranged to work into or through a recess in the outer rim or edge of the pillar-plate, said end being urged outward by a spring, the clickspring .9 being preferably made to serve also this purpose.

As more clearly shown in Fig. 9, the screw it, by which the eseapement-platform is held in place, is formed with a tapering or pointed end, and, as shown in Figs. 6 and 7, this pointed or tapered end is passed through the pillar-plate almost exactly over the outer edge of the long arm of the lever D, so that as the screw is turned to its seat the point is caused to press inward the long arm of the lever, thereby causing the short arm to move outward and disengage the pin 19 from the teeth of the fourth wheel, 0, and to hold it away therefrom, while the withdrawal of said screw permits the lever D, pressed by the spring 8, to move in the reverse direction and to lock the fourth wheel. It will thus be seen that it is impossible for any injury to occur to the train in removing the eseapement.

By arranging the end of the lever D to work in the recess in the rim itis prevented from being pressed outward from the face of the pillar-plate, while the shoulder g prevents the lever from being moved too far.

By referring to Figs. 3 and 10 it will be seen that either a straight-line or angular escapement may be with equal facility used in my construction, and the same is true with reference to pocket-chronometers, whether the escape-ment be of the English or the Swiss pattern.

Having thus described my invention, what I claim is 1. In combination with the pillar-plate provided with the flanged screw 1, the platform B. having the lip a and stud h, and secured to the pillar-plate by'a screw, it, as described.

2. The combination of the lever D, clickspring 8, and screw 7c, substantially as and for the purpose described.

3. In combination with a pillar-plate having a recessed rim, the lever D, having its end shouldered and working in sa d recess, and the screw is, all arranged and operating substantially as described.

4. The escapementplatform B, provided with the lip 60, recesses m 11.,and projection 0, as shown.

5. In combination with the pillar-plate of a watch, a detachable escapement-plattbrm and a fastening-screw located in rear of the balance-cock, whereby the cock is made to protect the escapementand the use of an angular or ehronometer escapement is permitted.

FREDERICK FITT.

Witnesses J. OoUasoLLE, L. J. OoURsoLLEs. 

